Short answer: the Ultimate Ears Boom 4 on measured sound quality, the Tozo PA2 on price, though neither ranks well in its class. The Ultimate Ears Boom 4 ranks #99 of 150 medium speakers, rated 2.9/5, at $109.99. The Tozo PA2 ranks #118, rated 2.5/5, at $39.99, $70 cheaper. Both are rated below 3.0/5 among the 150 medium speakers; for better sound, the Earfun Uboom L ranks #1 at $49.79.
Why pick the Ultimate Ears Boom 4: IP67 rated, floats, and finally charges via USB-C instead of the older Booms’ Micro-USB. Watch for: Not much improvement over the old ones.
The case for the Tozo PA2: IPX8 rated, rugged fabric-wrapped design. The tradeoff: Quite a bit of bass distortion thudding as you turn the volume up.
Buy the Ultimate Ears Boom 4 when sound quality outweighs the price for you, and the Tozo PA2 when the price outweighs sound quality instead.
Battery life favors the Tozo PA2: rated for 25 hours against 15 hours for the Ultimate Ears Boom 4.
Still deciding? The full Portable Bluetooth rankings cover every ranked option.
Specifications Side By Side
| Ultimate Ears Boom 4 | Tozo PA2 | |
|---|---|---|
| Price | $109.99 | $39.99 |
| Ranked | #99 of 150 in Medium Size Portable Bluetooth Speakers | #118 of 150 in Medium Size Portable Bluetooth Speakers |
| App | Yes | Yes (TOZO App) |
| Battery Life | 15 hours (Manufacturer specified) | 25 hours (Manufacturer specified) |
| IP Rating | IP67 | IPX8 |
| Power Input | USB-C | USB-C |
| Stereo | Yes | Yes |
| Omnidirectional | No | No |
| Weight | 1.4 lbs (620 g) | 1.2 lbs (540 g) |
| Bluetooth | Yes | Yes |
| Bluetooth Version | 5.1 | 5.3 |
| Dimensions | 7.2” x 2.9” x 2.9” (184 x 73 x 73 mm) | 7.1” x 2.8” x 3” (180 x 70 x 76 mm) |
| Drivers | 2x 1.57” (40mm) active drivers + 2x 1.81” x 2.57” (46.1 x 65.2mm) passive radiators | 2x 1.7-inch full-range drivers + 2x passive radiators (44x49mm each) |
| TWS | Yes | Yes |
| EQ | Yes (via app) | Yes (16 EQ modes via app) |
| Built-in Microphone | No | Yes |
| Power Bank | No | - |
| Aux Input | No | No |
| Maximum SPL | 85dBC (Manufacturer specified) | - |
| Digital Aux Input | No | No |
| Bluetooth Codecs | SBC | SBC, AAC |
| Strap | Yes (built-in loop) | - |
| Amplifier Power | - | 16W |
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- Soundcore Boost “upgraded” 2021 vs Ultimate Ears Boom 4
- Ultimate Ears Boom 4 vs Minirig 4
Prices on this page were last checked September 30, 2026 at 2:57 PM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.
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The Two Speakers In Full
Ultimate Ears Boom 4: $109.99 Amazon eBay
Older model: the Ultimate Ears Boom 3 (ranked lower, rated 2.9/5).
Pros: IP67 rated, floats, and finally charges via USB-C instead of the older Booms’ Micro-USB. 15 hour battery. Customizable EQ and speaker-pairing via the UE app.
Cons: Not much improvement over the old ones. Weak bass extension and thuddy bass. Gets distorted above 90%
Full Ultimate Ears Boom 4 review and specifications →
| App | Yes |
|---|---|
| Aux Input | No |
| Battery Life | 15 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 5.1 |
| Built-in Microphone | No |
| Digital Aux Input | No |
| Dimensions | 7.2” x 2.9” x 2.9” (184 x 73 x 73 mm) |
| Drivers | 2x 1.57” (40mm) active drivers + 2x 1.81” x 2.57” (46.1 x 65.2mm) passive radiators |
| EQ | Yes (via app) |
| IP Rating | IP67 |
| Maximum SPL | 85dBC (Manufacturer specified) |
| Omnidirectional | No |
| Power Bank | No |
| Power Input | USB-C |
| Stereo | Yes |
| Strap | Yes (built-in loop) |
| TWS | Yes |
| Weight | 1.4 lbs (620 g) |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
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- See all 133 comparisons
Tozo PA2: $39.99 Amazon eBay
Pros: IPX8 rated, rugged fabric-wrapped design. App offers 16 EQ modes and TWS dual-pairing with a second PA2.
Cons: Quite a bit of bass distortion thudding as you turn the volume up. Bass not that deep. The Tozo PA1 totally outclasses it.
Full Tozo PA2 review and specifications →
| Amplifier Power | 16W |
|---|---|
| App | Yes (TOZO App) |
| Aux Input | No |
| Battery Life | 25 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC, AAC |
| Bluetooth Version | 5.3 |
| Built-in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 7.1” x 2.8” x 3” (180 x 70 x 76 mm) |
| Drivers | 2x 1.7-inch full-range drivers + 2x passive radiators (44x49mm each) |
| EQ | Yes (16 EQ modes via app) |
| IP Rating | IPX8 |
| Omnidirectional | No |
| Power Input | USB-C |
| Stereo | Yes |
| TWS | Yes |
| Weight | 1.2 lbs (540 g) |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons